Oil Burner License Exam Questions and Answers, Latest Updated 2024/2025 (Verified Answers)

What is the first thing a tech should do when arriving at a no combustion call? - AnswerAsk how many times the customer reset the unit. What is the best long term solution for preventing a clogged nozzle? - Answer- -Remove any underground storage tanks. -Install a quality oil filter. -Cut the suction line 10" above the tank outlet to prevent sludge. Hot water and steam valves are interchangeable. - Answer- False When in the presence of a flame, a cad cell normally reads.. - Answer- 300-1000 ohms If a pump is used to bring oil to a level higher than the tank, an oil safety valve is required. - Answer- True On a call where a hydronic heat system is putting out too much heat on the stack, the issue may be.. - Answer- -Too much draft. -Not enough combustion air in the equipment room. -Air leakage into chamber. A high CO2 reading is caused by.. - Answer- Incomplete combustion An often overlooked cause of a high CO2 reading is.. - Answer- Not enough combustion air in the equipment room. When multiple pumps are wired together in a heating system, they should be wired in.. - Answer- parallel In a series circuit.. - Answer- Current has one path. When 2 burners are connected to the same chimney.. - Answer- Sufficient draft must be obtained to operate both units. The ignition transformer is located.. - Answer- In the primary control. When safeties are wired in series one safety will affect the operation of the others. - Answer- True Oil Burner License Exam Questions and Answers, Latest Updated 2024/2025 (Verified Answers) A stack switch is no longer allowed to be installed or replaced because.. - Answer- It's safety cutout time is higher than what is now required. What is a power venter and what does it do? - Answer- An electrical device that sends fluid gases into the chimney connector. A burner in a confined space using 1 GPH of #2 fuel oil requires what size permanent opening for combustion air? - Answer- 140" The difference between an adjustable flame retention burner and a fixed flame retention burner is? - Answer- Air inlets can be adjusted Ignitor position can be adjusted Fuel can be adjusted Oil tank design, construction, installation and testing shall be in accordance with.. - Answer- 527 CMR 9.0 Heat is a form of.. - Answer- Energy If a burner is operational but the circulator pump isn't running.. - Answer- The pump relay is not working correctly A method of dealing with low viscosity/cold temps with #2 oil? - Answer- Increase pump pressure/ decrease nozzle size What is needed at the outlet of an oil tank? - Answer- Thermal safety valve Where do you obtain an installation permit for oil burners? - Answer- Fire Dept How many Btu's approximately in 1 gal of #2 fuel oil? - Answer- 140,000 btu's Solid state ignition is superior to spark because - Answer- It is not affected by reduced voltage What is an installation? - Answer- The complete setting in place, ready for operation, of an oil burner appliance together with its accessories and equipment. How far must a power vent terminate from an opening or window? - Answer- 4' A pump in a one pipe system that is full of air can be self purged. - Answer- False List the minimum size of an oil supply line. - Answer- 3/8" A material with electrons so loose it allows voltage to pass with little or no resistance.. - Answer- Is a conductor If a high limit goes off, what does a low water switch do? - Answer- Maintains water temperature What is flashpoint an indicator of? - Answer- Minimum temperature oil will ignite but not continue to burn. What travels on the inside of the wire? - Answer- Volts What does readily accessible mean pertaining to oil burning equipment? - AnswerCapable of being reached easily and quickly for operation, maintenance or inspection. What is the minimum vent pipe on an oil tank? - Answer- 1 1/4" What causes corrosion on a flue pipe? - Answer- When the flue pipe is operating below the dew point temperature. What are the methods to prevent oil waxing? - Answer- Put additives in the fuel. Add an oil line heater. Cut with #1 fuel or kerosene. What is the maximum tank size allowed inside unenclosed? - Answer- 660 gal What is the purpose of a delayed oil valve? - Answer- Allows time for the oil pump to get up to speed. Delays oil flow to the nozzle. On a call where a hydronic heat system is putting out too much heat, the issue could be? - Answer- A shorted out thermostat. When measuring a cad cell with the burner running and the ff terminals jumped out, what should the cad cell reading be? - Answer- 1600 ohms What are the possible causes of soot at or near the power venter? - Answer- Incomplete combustion What is a possible side effect of air in a nozzle line? - Answer- Soot What is the cause if the cad cell is tripped on safety? - Answer- Dirty cad cell Faulty cad cell No flame present If a boiler is running but the water temperature is low? - Answer- Undersized nozzle If a boiler is at 30 psi and the relief valve opens? - Answer- Expansion tank is undersized Tank bladder is perforated Tankless coil is leaking Atomizing type burners were designed to burn which type of fuel? - Answer- #2 oil One gallon of #2 fuel oil contains approximately: - Answer- 140,000 BTU's Pour point problems with outside above ground fuel tanks can be partially relived by: - Answer- -Relocating the outside fuel filters and strainers to the inside -Switching to #1 fuel oil -Reducing the pour point of #2 fuel oil by blending it with #1 fuel oil A fuel oil storage tank cannot be installed: - Answer- In the furnace room within 5 feet of the heating unit The primary purpose of a fuel pump in a high pressure burner is to: - Answer- -Deliver oil at a constant and regulated pressure to the nozzle -Move oil from the tank to the pump -Provide a screen to filter the oil If the vacuum reading is substantially above the calculated reading, (with the burner running) the cause may be: - Answer- -Plugged fuel filter -Kinked oil supply line -Check valve sticking With most new flame retention burners, the motor speed is: - Answer- 3400 rpm To check for a proper nozzle line cut-off, the pressure gauge is installed in the: - Answer- Nozzle port Fuel units are generally set at the factory at: - Answer- 100 psi The oil burner nozzle in a high pressure burner performs the following functions: - Answer- -Atomizes the oil -Provides a pattern of oil spray -Delivers a fixed amount of oil The nozzle flow rate, spray angle and pattern are directly related to: - Answer- - Tangential slots -Swirl chamber -Orifice Cold oil or high viscosity problems may be eliminated by: - Answer- -Increasing the pump pressure and reducing the nozzle size -Installing a nozzle line pre-heater The following conditions or elements affect choosing the correct nozzle spray patterns: - Answer- -Air-oil mixing design of the burner -Shape of the chamber Which condition affects nozzle spray droplet size? - Answer- Fuel pump pressure To burn one pound of fuel oil, how many pounds of air does it take? - Answer- 14.4 lbs A layer of soot 1/16" thick will increase fuel consumption by: - Answer- 4% When sizing a combustion chamber for a firing rate of 1.00 gph, you should provide a minimum floor space of: - Answer- Between 80 to 100 square inches The most common type of burner design today is the: - Answer- High pressure atomizing Poor draft due to a faulty chimney may be improved by installing a good: - AnswerDraft inducer The draft differential produced by chimneys is best measured with a draft gauge in: - Answer- Inches of water column The most important draft measurement to be taken on any oil-fired unit is: - Answer- - The draft at the breach -The draft over the fire The proper location to install a draft inducer is: - Answer- In the flue pipe between the draft regulator and the chimney Using combustion test instruments to measure the composition and temperature of the flue gas as they leave the heating unit will indicate the: - Answer- Steady state efficiency The holes that are provided in the flue pipe for combustion testing must be: - AnswerBetween the heating unit and the draft regulator When using a pump type smoke tester, 10 full strokes are necessary to: - Answer- Draw the proper amount of fluegas past the paper The fluid in a CO2 tester is good for how many tests? - Answer- For about 200 tests In an electric circuit in order for the wattage to remain the same if the voltage drops, the amperage must: - Answer- Increase When applying current through a conductor that is wound in a coil the magnetic lines of force created are used in - Answer- -Solenoid valve -Relay -Electric motor If in an average 15 amp residential heating circuit, the fuse occasionally blows, you should: - Answer- Use an amp meter to check out the system To determine the "electrical potential" available at any given point in a circuit you should use a: - Answer- Voltmeter Burner ignition systems normally operate at what primary voltage? - Answer- 120 V Burner ignition transformers operate at what secondary voltage range? - Answer10,000 to 14,000 V In which type of systems does the ignition transformer stay on for the full time the burner is running? - Answer- Intermittent A typical ignition transformer is of what type? - Answer- Step-up During a normal start-up, when current is applied to a split phase burner motor with an open centrifugal switch: - Answer- -The motor will not start -The primary control will time out and trip on safety The _______ switch opens when the motor has almost reached full speed - AnswerCentrifugal The most popular speed (S) used in American made burners are: - Answer- -1725 rpm -3450 rpm Because burner fans have beveled blades any dirt or lint in the blade will: - AnswerReduce the amount of air for combustion The fan limit control on a warm air unit is used to: - Answer- -Shut off the burner at a predetermined temperature -Start the blower at a predetermined temperature -Stop the blower at a predetermined temperature In all residential oil heating systems, the high limit control must be: - Answer- Line voltage and wired in series with the primary control Low voltage thermostats are more widely used van line voltage thermostats because: - Answer- They are more sensitive to ambient temperature When a thermostat appears to be out of calibration, before recalibration it is important to first: - Answer- -Be sure the thermostat is level -Check to see that the hole behind the thermostat is sealed off properly -Be sure that the thermostat is acclimated to the room temperature The primary control must be capable of: - Answer- -Reacting to the absence of flame -Controlling the ignition and motor -Locking out on safety in the event of flame failure When an interrupted ignition stack mounted primary is energized call - Answer- The motor and ignition relays pull in together When using a remote mounted heat sensing primary control, the flame detector is often referred to as: - Answer- Pyrostat Because of the cad cell eye's limited sensing range, it can only be used effectively to: - Answer- Monitor an oil flame It has been established that _________ of steam is sufficient to operate any residential one-pipe steam system. - Answer- 2 psi When installing a replacement steam boiler, it is important to: - Answer- Follow the manufacturers piping instruction In the early 1900's the ________ was invented to prevent water from leaving the steam boiler should a return line spring a leak. - Answer- Hartford Loop One of the reasons a radiator on a two pipe system fails to heat may be: - Answer- A faulty thermostat trap A steam pigtail should always be installed between the pressuretrol and the boiler to: - Answer- Place a water seal between the boiler and the pressuretrol In a one-pipe system, the minimum distance between the water level and the bottom of the lowest steam carrying pipe is: - Answer- 28 inches To prevent scalding temperatures at the domestic water fixtures when using a tankless coil, it is important to install a: - Answer- Tempering valve A typical residential zone valve for a hot water heating system normally operates on: - Answer- 24 volts In most residential hot water heating systems, the design temperature difference between the supply and return water is: - Answer- 20° F To properly size a zone circulator, you must know the following: - Answer- The gpm and feet of head of the piping The _____ is used to prevent gravity circulation through the system when the boiler maintains temperature. - Answer- Flow control valve Tribulations in the tubes of a fire tube boiler: - Answer- Increase efficiency In a forced warm air system, the return air duct size should never be less than ______ of the supply air duct size. - Answer- 80 percent On a cold day, the burner is cycling on and off the flame is sufficient but the complaint of insufficient heat may be caused by: - Answer- Faulty or improperly set high limit Short cycling of the burner can be caused by: - Answer- -The heat anticipator not set properly -High limit set too low -Oversized equipment The proper location for the vacuum gauge when testing a fuel unit and supply line is: - Answer- A suction port One reason oil would drop from the nozzle after the burner shuts down is: - Answer- A faulty fuel unit cut-off On a burner that has been properly set up and adjusted, yet will experience an occasional hard start or puff back, the problem may be: - Answer- Low voltage input to the transformer Off-cycle heat losses include: - Answer- -Chimney draft -Jacket loss By replacing an old style burner with a new retention head burner, off-cycle losses are reduced because: - Answer- It restricts the draft induced airflow through the burner. A simple, effective, yet inexpensive way to increase on-cycle system efficiency is to: - Answer- Match the nozzle to the heating load The ______ are important for both on and off cycle efficiency in a fire tube boiler. - Answer- Combustion chambers Before lowering the temperature of a hot water boiler, consideration must be given to the: - Answer- Design of the heating system The boiler or furnace is not the only source of heat loss. The heating system can lose heat through: - Answer- -Uninsulated steam pipe -Uninsulated hot water pipe -Uninsulated warm air ducts A condition often overlooked on a call involving odors is: - Answer- Insufficient air in the boiler room One method of removing oil and dirt from a newly installed steam boiler is to: - AnswerSkim the boiler through a nipple at the water level after a few days If a cad cell is "seeing" light when the thermostat is connected to the T-T terminals calls for heat: - Answer- The primary control will not energize A reverse acting aquastat is used in a hydronic system to: - Answer- Stop the circulator when the water temperature falls below a preset temperature Burner air fans are manufactured to very close tolerances because an unbalanced fan can: - Answer- -Put a strain on motor bearings -Create vibrations When wiring a burner for intermittent ignition using a stack type primary control, the transformer is wired to terminals 2 and - Answer- 3